This invention relates generally to tractors having an operator's station rotatable about an arc of approximately 180.degree. to permit proper orientation of the operator for convenient operation of the tractor in opposing directions and, more particularly, to an actuating linkage operably associated with the control lever for selecting the speed and direction of travel of the hydrostatically driven tractor.
A hydrostatically driven tractor of the type shown in U.S. Pat. Nos. 4,372,341 and in 4,822,962, is operable in opposing directions with equal efficiency. To facilitate the operation of such a tractor, the operator's seat and steering mechanism are formed as a part of a console pivotally supported from the frame of the vehicle to permit rotation of the console about a generally vertical pivot axis to enable a positioning of the operator sitting in the seat cushion to face the direction of travel irrespective of which opposing direction is considered to be forward.
The speed and direction of travel of the hydrostatically driven tractor is controlled from a single control lever connected by a linkage to a hydraulic system to control the flow of hydraulic fluid therethrough for powering movement of the tractor. This control lever is typically stationarily mounted relative to the frame of the tractor within reach of the operator positioned in the operator's seat so that the direction of travel of the vehicle corresponds to the direction the control lever is moved to effect appropriate control of the hydraulic system. However, whenever the operator rotates the operator's station to face in the opposing direction, the control lever becomes positioned on the opposing side of the operator's seat so that the operator must use the opposite hand to manipulate the movement of the control lever.
It would be desirable to mount the control lever for operatively controlling the movement of the tractor with the operator seat in such a manner that the control lever is pivotally moveable with the seat in fixed relation thereto so that the control lever is maintained in a fixed orientation relative to the seat permitting the operator to use the same hand to operate the control lever irrespective of the rotated position of the operator's station. However, it would also be desirable to provide an actuation linkage interconnecting the control lever and the hydraulic system so that the direction of movement of the tractor will correspond to the direction of movement of the control lever irrespective of the rotated position of the operator's station.